Numerical type
The number of values of k for which the equation x^2 - 3x + k = 0 has two distinct roots lying
in the interval (0, 1) is
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Answer:
x²- 3x+k=0.
D=3
2 −4k=9−4k. For distinct real roots, 9−4k≥0 or k≤49
or k≤2.25 ...(i)
Now the roots of the above equation is given by
x
1= 23+ 9−4k
and x 2 =23− 9−4k
Now
0≤x
1 ≤1
0≤ 23+ 9−4k≤1
0≤3+ 9−4k ≤2−3≤ 9−4k ≤−1 ....(ii)
0≤x 2 ≤1
0≤ 23− 9−4k ≤1
0≤3− 9−4k ≤2−3≤− 9−4k ≤−1
3≥ 9−4k ≥1 ....(iii)
From (ii) and (iii),
9≥9−4k≥1
0≥−4k≥−8
0≤k≤2
Also, from (i),k≤2.25
Hence
k∈[0,2].
Now there are infinite real numbers between [0,2], hence there are infinite possible value of k.
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